Articles tagged with Human Fertilization
Researchers discovered that birds have normally developing penises in early embryos but lose them through a genetic program, suggesting possible benefits for reproductive control. The study highlights the importance of programmed cell death in developmental processes and may provide insights into medical questions.
Researchers found a cellular signaling system that responds to THC and anandamide regulates sperm functions required for fertilization in humans. Heavy marijuana users may jeopardize fertility by overloading this natural signaling system.
Researchers found that fertilized eggs attach themselves to the womb six to 12 days after ovulation, with implantation occurring on day eight being the most successful. The later the attachment takes place, the more likely a pregnancy will end on its own. Day eight appears to be the optimal time for successful implantation.
Fetuses that implant late in the uterus have a higher risk of dying in the first weeks of pregnancy. The study found that if a fertilized egg implanted on or after day 12, it had an increased chance of loss, with risks reaching as high as 82%. Daily urine testing revealed that these lost fetuses tended to implant later than those that ...